Merge pull request #2016 from pbiering/server-delay

Server delay

CHANGELOG.md

@@ -7,6 +7,7 @@
 * Cleanup: deprecate config option 'ldap_use_ssl' for good
 * Performance: improve `path_to_filesystem()`
 * Performance: preload access rights from file
+* Add: [server] delay_on_error option
 
 ## 3.6.1
 

DOCUMENTATION.md

@@ -831,6 +831,14 @@ The maximum number of parallel connections. Set to `0` to disable the limit.
 
 Default: `8`
 
+##### delay_on_error
+
+_(>= 3.7.0)_
+
+Base delay in case of error response (seconds)
+
+Default: `0.01`
+
 ##### max_content_length
 
 The maximum size of the request body. (bytes)

config

@@ -21,6 +21,9 @@
 # Max parallel connections
 #max_connections = 8
 
+# Base delay in case of error response (seconds)
+#delay_on_error = 0.01
+
 # Max size of request body (bytes), default: 100 Mbyte
 # In case of using a reverse proxy in front of check also there related option
 #max_content_length = 100000000

radicale/app/__init__.py

@@ -3,7 +3,7 @@
 # Copyright © 2008 Pascal Halter
 # Copyright © 2008-2017 Guillaume Ayoub
 # Copyright © 2017-2019 Unrud <unrud@outlook.com>
-# Copyright © 2024-2025 Peter Bieringer <pb@bieringer.de>
+# Copyright © 2024-2026 Peter Bieringer <pb@bieringer.de>
 #
 # This library is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -72,6 +72,7 @@ class Application(ApplicationPartDelete, ApplicationPartHead,
 
     _mask_passwords: bool
     _auth_delay: float
+    _delay_on_error: float
     _internal_server: bool
     _max_content_length: int
     _max_resource_size: int
@@ -97,6 +98,8 @@ class Application(ApplicationPartDelete, ApplicationPartHead,
         """
         super().__init__(configuration)
         self._mask_passwords = configuration.get("logging", "mask_passwords")
+        self._delay_on_error = configuration.get("server", "delay_on_error")
+        logger.info("delay_on_error set to: %.3f seconds", self._delay_on_error)
         self._max_content_length = configuration.get("server", "max_content_length")
         self._max_resource_size = configuration.get("server", "max_resource_size")
         logger.info("max_content_length set to: %d bytes (%sbytes)", self._max_content_length, utils.format_unit(self._max_content_length, binary=True))
@@ -304,6 +307,15 @@ class Application(ApplicationPartDelete, ApplicationPartHead,
                 flags_text = " (" + " ".join(flags) + ")"
             else:
                 flags_text = ""
+            # delay on error
+            if status >= 400:
+                if self._delay_on_error > 0:
+                    random_delay = self._delay_on_error * (1 + random.random())
+                    if status >= 500:
+                        random_delay = 2 * random_delay
+                    if logger.isEnabledFor(logging.DEBUG):
+                        logger.debug("Response delay triggered by result code: %d -> %0.3f seconds", status, random_delay)
+                    time.sleep(random_delay)
             if answer is not None:
                 logger.info("%s response status for %r%s in %.3f seconds %s %s bytes%s: %s",
                             request_method, unsafe_path, depthinfo,

radicale/config.py

@@ -171,6 +171,10 @@ DEFAULT_CONFIG_SCHEMA: types.CONFIG_SCHEMA = OrderedDict([
             "value": "100000000",
             "help": "maximum size of request body in bytes (default: 100 Mbyte)",
             "type": positive_int}),
+        ("delay_on_error", {
+            "value": "0.01",
+            "help": "base delay in case of error response (seconds)",
+            "type": positive_float}),
         ("max_resource_size", {
             "value": "10000000",
             "help": "maximum size of resource (default: 10 Mbyte)",

radicale/tests/test_auth.py

@@ -69,8 +69,10 @@ class TestBaseAuthRequests(BaseTest):
         with open(htpasswd_file_path, "w", encoding=encoding) as f:
             f.write(htpasswd_content)
         self.configure({"auth": {"type": "htpasswd",
+                                 "delay": 0,
                                  "htpasswd_filename": htpasswd_file_path,
-                                 "htpasswd_encryption": htpasswd_encryption}})
+                                 "htpasswd_encryption": htpasswd_encryption},
+                        "server": {"delay_on_error": 0}})
         if test_matrix == "ascii":
             test_matrix = (("tmp", "bepo", True), ("tmp", "tmp", False),
                            ("tmp", "", False), ("unk", "unk", False),

radicale/tests/test_base.py

@@ -73,6 +73,7 @@ collection: .*
 permissions: RrWw""")
         self.configure({"rights": {"file": rights_file_path,
                                    "type": "from_file"},
+                        "server": {"delay_on_error": 0},
                         "logging": {"request_header_on_debug": "True",
                                     "request_content_on_debug": "True",
                                     "response_header_on_debug": "True",